Fire-alarm-transmitter movement.



W. R. HAMILTON. FIRE ALARM TRANSMITTER MOVEMENT. APPLICATION FILED APR. 12, 1913.

1 1 26,200. Patented Jan. 26, 1915.

[THE NORRIS PETERS CO.. PHurO Lrrnn. wAsnlm, ION D c.

NTTED STATES PATENT OFFICE.

VILLIAM It. HAMILTON, OF MONTREAL, QUEBEC, CANADA, ASSIGNOR TO THE DOMINION GRESHAM GUARANTEE & CASUALTY COMPANY, OF MONTREAL, CANADA, A CORPO- RATION OF CANADA.

FIRE-ALARM-TRANSMITTER MOVEMENT.

Specification of Letters Patent.

Patented Jan. 26, 1915.

Application filed April 12, 1913. Serial No. 760,809.

To all whom it may concern.

Be it known that I, WVILLIAM R. I'IAMIL- ion, a subject of the King of Great Britain, residing at the city of Montreal, in the Province of Quebec, and Dominion of Canada, have invented certain new and useful Improvements in Fire-Alarm-Transmitter Movements, of which the following is a full, clear, and exact description.

This invention relates to improvements in transmitters or similar instruments for use in connection with water sprinkler, fire alarm, burglar or similar automatic signaling systems, and particularly for use in connection with any-type of automatic signal transmitter arranged to send two separate and distinct signals.

The invention consists in providing the transmitter with two tripping magnets of different resistances; mechanically connecting the armatures of these magnets in such a way that the dropping of one armature by gravity will operate the other armature to release the transmitter; and in providing means for mechanically raising the armature of the high resistance magnet to restore the transmitter to normal condition.

In the drawing the figure is a front elevation of a transmitter arranged according to the present invention.

Referring more particularly to the drawing, 5 designates the frame of the transmitter movement in which is mounted a control lever 6 having a stop 7 arranged in the path of the fan 8. At the lower part of the transmitter an electro-magnet 9 is provided having an armature 10 secured to the lever 6, so that when the magnet draws up its armature, the lever 6 will be shifted to withdraw the stop 7 from the path of the fan 8, and thus release the transmitter movement. One arm of a lever 11, carried on the same pivot as the lever 6, is secured to the armature 10, and the apposite arm projects upwardly a suitable distance preferably into engagement with a cam (not shown) mounted with the signal apparatus 12. A small spring 13 may be provided to normally hold the armature 10 away from the magnet 9.

On the upper part of the transmitter frame, an electro-magnet 14 is provided in inverted position, 6. 0., with its armature 15 at the bottom. This armature is mounted 011 one arm of a bell-crank lever 16, the

other arm of which is provided with a pin 17 arranged to engage the lever 11, so that when the armature 15 drops the control lever 16 will be operated through the medium of the levers 16 and 11, and the armature 10, as will be readily seen from the drawing. At a suitable point, the arm of the lever 16 carrying the armature 15 is provided with a pin 18 adapted to be engaged by a cam 19 mounted with the commutator 20 of the transmitter. This cam is provided with a peripheral notch or recess 21 which is positioned under the pin 18 whenever the transmitter is fully wound and at rest and inoperative, as shown in the drawing.

To enable the operation and purpose of the device to be readily understood, let it be supposed that the magnet 9 is connected in a fire detecting system and arranged to release the transmitter and hold it in released condition, so that the transmitter sends in its signal a certain number of times, for example, five, when the transmitter will be run down. This repetition of the signal five times denotes a fire alarm. Let it also be supposed that themagnet 14 is of higher resistance than the magnet 9, and is arranged in a closed circuit with all parts of the fire alarm signaling system and transmitter, and is also arranged to release the trans mitter to indicate a disordered condition. The mechanism previously described mechanically stops the transmitter when it has sent in its signal a lesser number of times than required for a fire signal, for example, only twice.

From the foregoing, it will be understood that in the case of a weak battery, the high resistance magnet will become inoperative and unable to hold up its armature, while there is still ample current strength to operate the low resistance magnet for the send ing of a fire alarm. Thus, a weakened battery will automatically send a trouble signal and the transmitter will be mechanically restored to normal, in readiness to send a fire alarm signal if such should be necessary before the weak battery has been renewed. When the magnet 14: becomes deenergized either by weakened battery or short circuit, its armature 15 falls by gravity and operates through the levers 16 and 11 to shift the control lever 6 and release the transmitter.

The main feature of this invention is, therefore, the mechanical restoration of the armatures to normal position. This restoration is eflected by the cam 19 which raises the armature 15 by engaging the pin 18 thereon, so that the armature is lifted up to its magnet 1-1 regardless of whether current is flowing through the magnet or not. In this way, the transmitter is automatically restored to condition for sending a fire signal immediately after the sending of a trouble signal. This mechanical restoration is of great importance for the reason that the transmitter would be inoperatii e for sending fire signals when slightly deranged or. equipped with aweak battery, it the restoration of the magnet 14 depended upon electrical energy. In the case of a weakened battery, the magnet 1 1 will often hold up its armature when it would be absolutely unable to lift the armature. The mechanical restoration of the armature 15 releases the lever 11, so that the spring 13 is enabled to pull the control lever 6 to bring its stop 7 in the path of the fan.

While the invention has been shown and described as applied to a specific form of transmitter and used for a specific purpose, this description must be taken as merely illustrative and not in any way limitative, since the device may be applied to numerous other forms of transmitters and signal systems.

While the movement has been shown to contain a pin bearing lever 16 and notched cam, it is obvious that the pin may be mounted on the cam instead of on the lever without departing in any way from the spirit of the invention.

Having thus described my invention, what I claim is 1. In a signal transmitter, the combination with a mechanical operating device and a control device therefor of a pair of magnets adapted to independently operate the control device, and means actuated by the mechanical operating device for automatically shifting the control device to stop the transmitter.

.2. In atransmitter, the combination with a mechanical motor and a control device therefor of a magnet arranged to operate the control device by drawing up its armature, a second magnet arranged to operate the control device by dropping its armature, and means operated by the motor 'for raising the armature of said second magnet to release the control device, and a spring for operating the control device to stop the motor.

3. In a transmitter, the combination of a mechanical motor and a control device therefor of a pair of magnets, an armature for one of said magnets arranged to operate the control device, an armature for the second magnet, a system of levers connecting the second armature with the control device whereby movement of the second armature operates the control device to start the motor, and a cam driven by the motor arranged to release said control device to stop the motor independently of the action ofthe second magnet.

4. In a transmitter or the like, the combination with a motor and a control device therefor of a lever secured to the control device, a second lever engaging the first lever, a magnet having its armature fixed to said second lever, whereby movement of the armature will operate the motor control device, a cam driven by the motor adapted to engage one of said levers to restore the control device to normal position, and a second magnet adapted to operate the control device independently of the first magnet or the mechanical restoring means.

5. In a transmitter, the combination with a mechanical motor and a control device therefor of a lever secured to said control device, a bell-crank lever adapted to engage said first lever, a magnet having its armature connected to said bell-crank lever whereby movement of the armature will operate the control device through said levers, a cam driven by the motor engageable with one of said levers to restore the control de vice to normal condition, and a second magnet adapted to operate the control device independently of the mechanical restoring means or the first magnet.

In witness whereof I have hereunto set my hand in the presenceof two witnesses.

WILLIAM R. HAMILTON. Vitnesses i STUART R. IV. ALLEN, G. M. MORELAND.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

